Literature

Hoa insists on that we need to understand problems
before to understand solutions. In fact, one of the goals
of Hoa is to teach their users, because learning without
understanding has no meaning and the experience shows that a comprehension
of a problem paired with generic solutions provides better results.

Hack book

The hack book contains (very) detailed explanations
about all the libraries of Hoa. Chapters are unordered. No library will have
a secret for you and you will be able to hack them!